title: Solvent-induced chirality control in the enantioseparation of 1-phenylethylamine via diastereomeric salt formation.
abstract: Solvent-induced chirality control in the enantioseparation of 1-phenylethylamine 1 by N-(p-toluenesulfonyl)-(S)-phenylalanine 2 via diastereomeric salt formation was studied. (S)-1·(S)-2 was preferentially crystallized as a less-soluble salt from aqueous alcohol, while (R)-1·(S)-2 salt was mainly obtained by addition of solvents with a six-membered ring such as dioxane, cyclohexane, tetrahydropyran, and cyclohexene to 2-propanol. Further investigations were carried out from the viewpoints of molecular structures, optical rotation measurement, and X-ray crystallographic analyses. Crystallographic analyses have revealed that incorporation of the six-membered ring solvent molecule in (R)-1·(S)-2 without hydrogen bonds changed the molecular conformation of (S)-2 to stabilize the salt, which changed the selectivity of 1 in the enantioseparation.
authors.affiliation: Department of Applied Chemistry, Saitama University, Saitama, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Kodama
authors.forename: Yuria
authors.initials: Y
authors.lastname: Kimura
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Shitara
authors.forename: Mikio
authors.initials: M
authors.lastname: Yasutake
authors.forename: Rumiko
authors.initials: R
authors.lastname: Sakurai
authors.forename: Takuji
authors.initials: T
authors.lastname: Hirose
mesh_terms: D019840:2-Propanol / Q000737:chemistry; D000596:Amino Acids / Q000737:chemistry; D018360:Crystallography, X-Ray / Q000379:methods*; D003510:Cyclohexanes / Q000737:chemistry; D053138:Cyclohexenes / Q000737:chemistry; D004146:Dioxanes / Q000737:chemistry; D005998:Glycine / Q000031:analogs & derivatives* / Q000737:chemistry; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008958:Models, Molecular; D008968:Molecular Conformation; D015394:Molecular Structure; D009904:Optical Rotation; D010627:Phenethylamines / Q000138:chemical synthesis / Q000737:chemistry* / Q000302:isolation & purification*; D010649:Phenylalanine / Q000031:analogs & derivatives* / Q000737:chemistry; D012492:Salts / Q000737:chemistry; D012997:Solvents / Q000737:chemistry*; D013237:Stereoisomerism; D014867:Water / Q000737:chemistry
chemical_list: D000596:Amino Acids; D003510:Cyclohexanes; D053138:Cyclohexenes; D004146:Dioxanes; C558718:N-(p-toluenesulfonyl)-(R)-phenylglycine; C558717:N-(p-toluenesulfonyl)-(S)-phenylalanine; C558719:N-benzenesulfonyl-(S)-phenylalanine; D010627:Phenethylamines; D012492:Salts; D012997:Solvents; D014867:Water; C052568:cyclohexene; D010649:Phenylalanine; C506365:Cyclohexane; C025223:1,4-dioxane; D019840:2-Propanol; D005998:Glycine